When treating various corneal conditions, such as, for example, keratoconus wherein corneal collagen crosslinking techniques are employed in connection with the photosensitizing of the human cornea with ultraviolet-A rays in order to strengthen the cornea, as well as other corneal diseases, such as, for example, infectious keratitis, severe inflammatory conditions, and ocular surface squamous neplasia, various solutions are required to be supplied to or cause the eye to be bathed within such solutions for a predetermined period of time. Riboflavin is a topical medication that is conventionally used for the purposes of corneal saturation in connection with corneal collagen crosslinking, and prior to the delivery of ultraviolet light to the cornea, so as to effectively increase the strength of the cornea and thereby treat keratoconus. The cornea can be weakened by various corneal diseases, one of which is keratoconus, which is a debilitating condition that is progressively degenerative, often bilateral, and can cause vision distortion, with multiple images, and sensitivity to light in early stages, and even blindness in more severe cases. When an eye develops keratoconus, the cornea becomes thinned and unstable, and in lieu of retaining its domed shape covering the front the eye, the cornea becomes more cone-shaped, thereby bending the light coming into the eye, in an unnatural manner, and thus leading to the aforenoted vision distortion problems. Sometimes, a corneal transplant is required.
Conventional treatment of keratoconus comprises the delivery of riboflavin to the affected cornea, and one conventional procedure may initially entail the removal of the epithelium or outermost layer of the cornea, or alternatively, the epithelium may be permitted to remain intact. In the past, it was preferred to remove the epithelium, the thinking or belief in the ophthalmological medical field being that better results could be achieved because the riboflavin would be more easily and more quickly absorbed by the cornea which, in turn, would lead to better treatment results. Current thinking or belief in the field, however, is that leaving the epithelium intact may be somewhat safer in that the epithelium layers does in fact provide an extra protective layer to the cornea, and that the end results achieved are basically the same as compared to those results achieved when the epithelium layer has been initially removed. In either case, riboflavin is applied to the eye, and after a predetermined period of time, which may vary from anywhere between five and forty-five minutes, the crosslinking techniques are begun by photosensitizing the cornea with ultraviolet light. It has been found that the ultraviolet light photosensitizing procedures can vary depending upon, for example, various protocols or variables. For example, the ultraviolet light may be applied continuously or in pulses. Alternatively, different concentrations of the light can also be employed. Conventionally, the photosensitizing procedures usually comprise time frames which may vary anywhere from between two and thirty minutes. In accordance with some prior art conventional solutions and techniques, various solutions have been proposed whereby such solutions resulted in enhanced retention times upon the cornea being achieved. Still other prior art conventional solutions have effectively been utilized to break down the epithelial layer or barrier of the cornea so as to facilitate enhanced penetration of the solutions into the cornea.
Regardless of which type of medications were being used, and regardless of whether or not the epithelial layer or barrier was removed or permitted to remain intact, it is also known that the intermittent delivery of topical anesthetic solutions to the patient has been required in order to ensure the patient's comfort throughout the procedure. This is also true in the case where other corneal diseases, conditions, or maladies such as, for example, infectious keratitis, severe inflammatory conditions, and ocular surface neoplasia, are also being treated by means of medications other than riboflavin such as, for example, suitable anti-infectives, anti-inflammatories, or anti-neoplasia agents. However, it can also be readily appreciated that in view of the fact that the application of the delivery of the topical anesthetic solutions to the eye, in connection with the treatment of any of the foregoing conditions, is intermittently performed, whereby the delivery of the particular medication will likewise necessarily be intermittent, the overall treatment process or procedure becomes substantially timely and labor-intensive in view of the additional fact that such procedures must be performed by trained medical personnel, and therefore, such treatment processes or procedures become relatively expensive. Furthermore, many of the medication or fluid application procedures require the patient to maintain his or her head in a predetermined position, or to maintain the eyes in a fixed mode, such as, for example, looking straight ahead, or still further, to have their eyelids held open for relatively long periods of time. All of these procedures may result in some level of discomfort to the patient, which is obviously not ideal. Accordingly, it would be desirable if a medicinal solution could be developed which would require less frequent human intervention and, at the same time, would effectively and simultaneously provide the maximum degree of comfort to the patient.
A need therefore exists in the art for a new and improved medicinal solution to be delivered to the eye that will resolve the aforenoted problems or drawbacks characteristic of the current state of the art and that will achieve the following overall objectives. More particularly, a need exists in the art for a new and improved medicinal solution to be delivered to the eye which will be cost effective, which will be significantly more comfortable for the patient, which eliminate the need for intermittent intervention procedures to be performed by medical personnel in connection with both the delivery of the medicinal solution for the actual treatment of the particular eye condition as well as the necessarily attendant anesthetic in order to render the patient as comfortable as possible, and which will enable a sufficient amount of medication or fluid to effectively be constantly or continuously delivered or applied to the eye.